This invention relates generally to a liquid crystal display device and more particularly to a liquid crystal display using a non-linear device and driven by an AC amplitude selective multiplexing signals in a two-frame method. More particularly, this invention relates to a multiplexing drive method for controlling variations in the effective voltage applied to the liquid crystal picture elements. Use of non-linear devices in conjunction with liquid crystal display elements has improved the driving duty for the elements. For example, varistors and MIM are known non-linear devices. Methods of driving a liquid crystal display device using such non-linear components have been the same as in a conventional driving method of the prior art. Namely, a generalized AC amplitude selective multiplexing signal is used wherein the ON and OFF states are alternatingly switched at the half point of a frame, that is, the so-called two-frame method. However, the conventional method has disadvantages in that the effective voltage applied to one picture element in the liquid crystal layer is likely to be influenced by the signals to other picture elements on the same signal line. As a result, a non-uniformity in display for different kinds of display patterns is due to variations in the effective voltage. Also, the conventional driving method is unsuited for a gray scale display and it is difficult to match the characteristics of the non-linear device.
What is needed is a liquid crystal display device of the matrix type having rows and columns of picture elements which provides uniform display quality regardless of the number of elements in a row which are lit and non-lit.